Hair clipper



Jan. 27, 1942. J. OSTER HAIR CLIPPER Filed Aug. 24, 1939 Patented Jan. 27, 1942 HAIR CLIPPER.

John Oster, Racine, Wis., assignor to John Oster Manufacturing Company, Racine, Wis., acorporation of Wisconsin Application August 24, 1939, Serial. No; 291,639

1 Claim.

Thisinvention relates to hair clippers and refers particularly to clippers of thetype forming the subject matter of the allowed application of John Oster, Serial No. 184,802, filed January 13, 1938, for Hair clipper, and issued December 5, 1939, as Patent No. 2,182,597.

In the past, it has been customary to provide hair clippers with a metal oscillatory driving lever for the movable cutter which had one end portion thereof engaged in a slot in the movable cutter to reciprocate the same when the lever wasoscillated.

The end portion of the lever engaged in the slot had to be designed to compensate for the differences in motion between the movable blade and the oscillatory driving end of the lever; and it was customary to round the end of the lever so that the sides of the slot were substantially tangent to the surfaces of the driving lever end which resulted in a line contact therebetween.

Inasmuch as the movable blade was formed of hardened steel and the end of the driving lever had a rotating as well as a sliding engagement with the sides of the slot in the blade, the end of the driving lever quickly became worn.

When such a condition existed, the clipper became extremely noisy in operation due to the metal end of the lever striking the sides of the movable cutter slot during each oscillation of the lever. eliminate the noise resulting from driving the blade in this manner; and as shown in the aforementioned application, one method was the substitution of a molded thermoplastic lever for the metal lever.

Due to the fact that the thermoplastic lever was softer than the metal driving lever and that the area of contact between its end and the movable blade was extremely small, the driving lever more quickly became worn, but noise was not noticeable until the lever end had worn to a considerable extent.

The clipper then became extremely noisy in operation, and a clattering sound resulted from the tendency of the lever end to flip the movable blade away from contact with the stationary blade.

This invention, therefore, has, as a general object, the provision of a noiseless driving connection between the oscillatory lever of the clipper and the movable blade thereof.

More particularly, this invention has as an object the provision of. a large flat. surface to surface; engagement between. the. driving lever end Various attempts have been made to and the movable, blade to insure longer andmore satisfactory operation of the clipper.

Another object of this invention is to provide the oscillatory lever of a hair clipper with a pivoted rectangular block at its outer end which engages the movable blade with a large surface to surface contact so that wear at the connection between the oscillatory lever and the movable blade is held to a minimum.

Another object of this invention is to provide the oscillatory lever of a hair clipper with a pivoted substantially square block, any two opposite sides of which are engageable in the slot of the movable blade to connect the same with the driving-lever. I

With the above and other objects in view which will appear as the description proceeds, this in.- vention resides in the novel construction, combination and arrangement of parts substantially as hereinafter described, and more particularly defined by the appended claim, it being under stood that such changes in the precise embodiment of the hereindisclosed invention may be made as come within the scope of the claim.

The accompanying drawing illustrates two complete examples of thephysical embodiment of the invention constructed in accordance with the best modes so far devised for, the practical application of the principles thereof, and in which-- Figure 1 is a'plan View of a conventional hair clipper with parts broken away to illustrate the application of this invention. thereto;

Figure 2 is a cross sectional view taken on the plane of the line 22 in Figure 1 having portions of. the body of the clipper in elevation;

Figure 3 is a perspective view of the movable cutter and the driving lever per se lookingat the I latory driving lever B pivoted on a stud 6' and drivingly connected with the motor (not shown.) through mechanism 1. One end 8 of the driving lever projects from the body of the clipper to lie adjacent to the blade assembly 9 at the forward endxof the body.

The blade assembly is composed of a stationary cutter l held in assembled relationship with the body of the clipper in any suitable manner or as disclosed in the aforementioned patent. The movable cutter ll overlies the face of the stationary cutter and is maintained in engagement therewith under spring tension by a U-shaped spring member l2 which is tionary cutter.

The closed end of the U-shaped spring member l2 has a substantially V-shaped ridge l3 facing the stationary cutter which engages in a correspondingly shaped groove [4 in the back of the movable cutter to constrain the same to motion in a straight line path parallel to the ridge.

At a medial portion, the movable cutter is provided with a slot l5 opening to one edge thereof, the side edges of which provide spaced parallel shoulders l6 at opposite sides thereof (see Figure 3). The shoulders I6 lie in parallel planes substantially perpendicular to the line of motion of the movable cutter.

The driving connection between the oscillatory lever B and the movable cutter is provided by a substantially rectangular block or driver l8 secured flatwise to the under side of the end 8 of the driving lever, as clearly shown in Figures 3 and 5.

A rivet l9 secures the driver in assembled relationship with the lever and is formed to permit relative rotation between the driver and the lever.

To this end, the rivet is provided with an enlarged shank 20 for the reception of th driver and has a reduced portion 2| extending therefrom to be received in a hole 22 in the driving lever end.

Thus, with the rivet positioned with the shoulder between the shank portions against the underside of the driving lever, the reduced end of the rivet is peaned against the opposite face of the lever; and as the thickness of the driver is less than the distance between thehead of the rivet and its shoulder, it follows that the driver is free to rotate about the rivet axis.

The outer end of the oscillatory lever holds the fixed to the stadriver l8 in the slot I5 of the movable cutter with two of its opposite sides 23 flatwise engaged with the shoulders 16 defined by the slot. Consequently, a large surface to surface contact exists between the driver and the shoulders I6, which provides a good driving connection substantially .free of noise over long periods of use.

became worn inasmuch as it rotated in the slot in addition to sliding therein.

In the embodiment of the invention illustrated in Figures 1 to 3, inclusive, the driver is shown formed as a substantially rectangular block shaped to engage in the slot in only one position.

When this construction is used, it is desirable to prevent the driver being assembled with the movable cutter with its narrow width engaged in the slot thereof. This follows from the fact that the driver must fit the slot with a substantially snug sliding engagement so as to insure good contact between the sides of the driver and the edges of the slot.

Consequently, in order to insure such proper assembly, one of the adjacent side edges on the narrow width of the driver is provided with a groove 24, the sides of which engage an abutment such as an upstruck portion of the lever or a lug 25 to limit rotation of the driver with respect to the lever.

The groove 24 is of such dimensions, however, that the sides thereof do not engage the lug 25 during the ordinary operation of the clinner.

If desired, a substantially square block may be used to drivingly connect the oscillatory lever with the movable cutter. This form of the invention is shown in Figure l, and it is apparent from the fact that the sides of the block 26 are of equal length that any two opposite sides may be engaged with the shoulders of the slot to drivingly connect the movable cutter with the oscillatory lever.

This form of the invention has the advantage of permitting adjustment of the driver as its sides engaging the shoulders of the slot become worn so that the unused sides may be engaged therein for good contact with the shoulders of the slot.

As in the preceding embodiment of the invention, the driver is freely pivotally connected with the end 8 of the oscillatory lever by the rivet l9; but it is noted that the rotation restricting groove 24 and lug 25 are unnecessary.

Inasmuch as the use of a driver of this type reduces wear to a minimum and substantially eliminates objectionable clattering noises, it is apparent that the driving lever may be of any suitable material. It is preferable, therefore, to form the lever as a stamping, as shown, which greatly reduces manufacturing costs.

When the lever is formed as a stamping, it is provided with an opening into which a bearing 28 is pressed so as to be nonrotatable therewith and which receives the stud 6' to pivotally mount the lever.

From the foregoing description taken in connection with the accompanying drawing, it will be readily apparent that this invention provides a simple but highly efficient connection between the oscillatory lever of a hair clipper and its movable cutter wherein wear at the connection and objectionable clattering noises are held to a minimum.

What I claim as my invention is:

In a hair clipper of the character described, the combination of: a movable cutter having a slot, the side edges of which are substantially parallel; means for guiding the movable cutter for substantially straight line motion in a defined plane with said side edges of the slot perpendicular to the line of motion of the movable cutter; an oscillatory driving lever having an end portion disposed flatwise and wholly above the movable cutter adjacent to the slot therein so that said end portion of the lever oscillates in a plane parallel to the plane of motion of the movable cutter; and a substantially square block pivotally connected to the underside of the driving lever for rotation relative thereto on an axis perpendicular to said parallel planes and snugly but slidably engaged in said slot of the movable cutter with opposite side edges of the block having a large surface to surface contact with said side edges of the slot, said block connecting the driving lever with the movable cutter so as to transmit driving force from the lever to the movable cutter for reciprocating the same, and being restricted by said side edges of the slot to sliding motion in said slot in a direction transverse to the line of motion of the movable cutter as the driving lever oscillates so as to minimize wear at the connection between the lever and the movable cutter; the pivotal connection between the block and the lever enabling the block to be turned on its axis to engage its other two opposite sides in the slot upon wearing of the block.

JOHN OSTER. 

